Nautel VX150, Operation & Maintenance Manual

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VX-LP OPERATIONS & MAINTENANCE MANUAL ROUTINE MAINTENANCE
PAGE 2.3.4 VERSION 1.0 2022-12-08
Performing On-Air Checks
You should check the on-air quality of the transmitter’s signal periodically. This check can be done
locally at the transmitter site, or remotely from another location in the transmitter’s coverage area.
Interval
Every 12 months, or as required by law.
Parts and Tools
 High-quality receiver compatible with the modulation scheme used on the transmitter.
Procedure
1. Monitor the transmitter signal to identify any problems:
 Use a high quality receiver to monitor audio quality.
 Check the spectral output of the transmitter. You can use the remote AUI's spectrum analyzer
as a basic indication of the transmitter's spectral output but always use a calibrated
measurement instrument when making measurements for regulatory compliance.
 Take a portable receiver to different locations in your coverage areas to identify any problems
with the antenna pattern or areas of localized interference.
2. Obtain the Critical Parameters sheet that was completed during factory testing and provided with
the transmitter. Use the transmitter’s AUI to compare current transmitter settings with those on the
Critical Parameters sheet.
NOTE
:
Nautel completes the Critical Parameters sheet with the transmitter terminated into a precision
50 ohm load. Measurements made on site into a dummy load or station antenna may not yield the
same readings. Slight variances are acceptable. The data is provided as a troubleshooting aid
.